Technical Booklet K Ventilation·Page 21·2.7
Extract ventilation in kitchens, bathrooms and other rooms
Kitchens, bathrooms, utility rooms and sanitary accommodation require mechanical or passive stack extract provisions with specified minimum extraction rates for both intermittent and continuous extract modes.
In other rooms (e.g. kitchens and bathrooms) the mechanical or passive stack extract provisions should provide adequate ventilation, although passive stack ventilation will take longer to purge the room.
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